Sabri, Hisham, et al. “Penjanaan Ekonomi Umat Islam Melalui Kaedah Istibdal Dalam Pembangunan Harta Wakaf”. The Journal of Muamalat and Islamic Finance Research, vol. 3, no. 1, Jan. 2006, pp. 203-22, https://jmifr.usim.edu.my/index.php/jmifr/article/view/61.